Aside from recording at 192kHz with the highest quality mics and recorders, how do you reinvigorate your slowed down/varispeeded sounds after they've lost most (or all) of their airy top end? (Varispeed, meaning slowing down playback in Soundminer, or using Pitch n' Time in Varispeed mode.) This effect is über-bad with older recordings or material from CD libraries. I find myself reaching for a basic EQ at times like this, boosting with a high-shelf from 5khz and up. What are your techniques?

CLARIFICATION:

Original question asked how to retain high frequencies when pitching down a file, rather than slowing down a file, thus the earlier answers.

Duplicate your track, and high pass all the top end you want to keep on one track while you pitch-shift the other one, possibly lowpassing out all the shifted top end. Basically, all you're doing is separating the track like a zipper.